FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
ass.c
Go to the documentation of this file.
1 /*
2  * SSA/ASS common functions
3  * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avcodec.h"
23 #include "ass.h"
24 #include "libavutil/avassert.h"
25 #include "libavutil/avstring.h"
26 #include "libavutil/bprint.h"
27 #include "libavutil/common.h"
28 
30  const char *font, int font_size,
31  int color, int back_color,
32  int bold, int italic, int underline,
33  int alignment)
34 {
36  "[Script Info]\r\n"
37  "ScriptType: v4.00+\r\n"
38  "PlayResX: 384\r\n"
39  "PlayResY: 288\r\n"
40  "\r\n"
41  "[V4+ Styles]\r\n"
42  "Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, AlphaLevel, Encoding\r\n"
43  "Style: Default,%s,%d,&H%x,&H%x,&H%x,&H%x,%d,%d,%d,1,1,0,%d,10,10,10,0,0\r\n"
44  "\r\n"
45  "[Events]\r\n"
46  "Format: Layer, Start, End, Style, Text\r\n",
47  font, font_size, color, color, back_color, back_color,
48  -bold, -italic, -underline, alignment);
49 
50  if (!avctx->subtitle_header)
51  return AVERROR(ENOMEM);
52  avctx->subtitle_header_size = strlen(avctx->subtitle_header);
53  return 0;
54 }
55 
57 {
66 }
67 
68 static void insert_ts(AVBPrint *buf, int ts)
69 {
70  if (ts == -1) {
71  av_bprintf(buf, "9:59:59.99,");
72  } else {
73  int h, m, s;
74 
75  h = ts/360000; ts -= 360000*h;
76  m = ts/ 6000; ts -= 6000*m;
77  s = ts/ 100; ts -= 100*s;
78  av_bprintf(buf, "%d:%02d:%02d.%02d,", h, m, s, ts);
79  }
80 }
81 
82 int ff_ass_bprint_dialog(AVBPrint *buf, const char *dialog,
83  int ts_start, int duration, int raw)
84 {
85  int dlen;
86 
87  if (!raw || raw == 2) {
88  long int layer = 0;
89 
90  if (raw == 2) {
91  /* skip ReadOrder */
92  dialog = strchr(dialog, ',');
93  if (!dialog)
94  return AVERROR_INVALIDDATA;
95  dialog++;
96 
97  /* extract Layer or Marked */
98  layer = strtol(dialog, (char**)&dialog, 10);
99  if (*dialog != ',')
100  return AVERROR_INVALIDDATA;
101  dialog++;
102  }
103  av_bprintf(buf, "Dialogue: %ld,", layer);
104  insert_ts(buf, ts_start);
105  insert_ts(buf, duration == -1 ? -1 : ts_start + duration);
106  if (raw != 2)
107  av_bprintf(buf, "Default,");
108  }
109 
110  dlen = strcspn(dialog, "\n");
111  dlen += dialog[dlen] == '\n';
112 
113  av_bprintf(buf, "%.*s", dlen, dialog);
114  if (raw == 2)
115  av_bprintf(buf, "\r\n");
116 
117  return dlen;
118 }
119 
120 int ff_ass_add_rect(AVSubtitle *sub, const char *dialog,
121  int ts_start, int duration, int raw)
122 {
123  AVBPrint buf;
124  int ret, dlen;
125  AVSubtitleRect **rects;
126 
128  if ((ret = ff_ass_bprint_dialog(&buf, dialog, ts_start, duration, raw)) < 0)
129  goto err;
130  dlen = ret;
131  if (!av_bprint_is_complete(&buf))
132  goto errnomem;
133 
134  rects = av_realloc(sub->rects, (sub->num_rects+1) * sizeof(*sub->rects));
135  if (!rects)
136  goto errnomem;
137  sub->rects = rects;
138  sub->end_display_time = FFMAX(sub->end_display_time, 10 * duration);
139  rects[sub->num_rects] = av_mallocz(sizeof(*rects[0]));
140  rects[sub->num_rects]->type = SUBTITLE_ASS;
141  ret = av_bprint_finalize(&buf, &rects[sub->num_rects]->ass);
142  if (ret < 0)
143  goto err;
144  sub->num_rects++;
145  return dlen;
146 
147 errnomem:
148  ret = AVERROR(ENOMEM);
149 err:
150  av_bprint_finalize(&buf, NULL);
151  return ret;
152 }
153 
154 void ff_ass_bprint_text_event(AVBPrint *buf, const char *p, int size,
155  const char *linebreaks, int keep_ass_markup)
156 {
157  const char *p_end = p + size;
158 
159  for (; p < p_end && *p; p++) {
160 
161  /* forced custom line breaks, not accounted as "normal" EOL */
162  if (linebreaks && strchr(linebreaks, *p)) {
163  av_bprintf(buf, "\\N");
164 
165  /* standard ASS escaping so random characters don't get mis-interpreted
166  * as ASS */
167  } else if (!keep_ass_markup && strchr("{}\\", *p)) {
168  av_bprintf(buf, "\\%c", *p);
169 
170  /* some packets might end abruptly (no \0 at the end, like for example
171  * in some cases of demuxing from a classic video container), some
172  * might be terminated with \n or \r\n which we have to remove (for
173  * consistency with those who haven't), and we also have to deal with
174  * evil cases such as \r at the end of the buffer (and no \0 terminated
175  * character) */
176  } else if (p[0] == '\n') {
177  /* some stuff left so we can insert a line break */
178  if (p < p_end - 1)
179  av_bprintf(buf, "\\N");
180  } else if (p[0] == '\r' && p < p_end - 1 && p[1] == '\n') {
181  /* \r followed by a \n, we can skip it. We don't insert the \N yet
182  * because we don't know if it is followed by more text */
183  continue;
184 
185  /* finally, a sane character */
186  } else {
187  av_bprint_chars(buf, *p, 1);
188  }
189  }
190  av_bprintf(buf, "\r\n");
191 }